While animal and fish protein provides power and growth factors that make us strong, the same growth and performance can be gained from a vegetarian or semi vegetarian diet and lifestyle as documented by the now famous author Michio Kushi who developed the concept of Macrobiotics.
By eating meat, the body becomes burdened by the weight of emotion the animal was carrying at the moment of its death combined along with all the toxins and environmental poisons accumulated in its body over a life time. It has been well documented that certain types of fish are high in mercury and that consuming them over a period of time has a negative impact on human health, similarly, we know of growth hormones fed to animals causing unpleasant side effects in people.
A diet with excess meat and especially a meat and starch diet with insufficient vegetables and fruits can lead to an imbalance of body chemistry, typically a heavy diet like this make the body more acid creating unnecessary stress which is often released aggressively.
All the great meditators including Buddha realised and emphasised that if you really want to move in deep meditation your body needs to be weightless, free, natural and flowing, unloaded of all this animal stuff. Meat as part of an animal body has a lower consciousness than humans which has a consciousness lowering effect and perhaps this is one reason why humankind in the present cycle cannot end the violence and struggle for power that dominates much of our world.
Many think that a diet based on meat and potatoes is more likely to cause colon cancer.
Hormones in meats
Effects of animal growth hormones in people